Comments

calls from a large flock (at times over 100) swirling over the canyon with the waterfall. The first couple of chorus calls are from the largest groups, with smaller groups and even single birds calling later in the cut.

Observation details

Coming in to and roosting at a large communal roost at the falls. The flock would swoop around over our heads and back down the valley repeatedly, getting gradually smaller until they had all entered the roost site. Some apparent young birds without white napes seen at the roost, and two eggs (abandoned?).